Question

A person has a power of 200 W in pushing a 75 N box to a distance of 20 m. How
much time did it take to push the box?

Answer 1

Answer:

7.5s

Explanation:

work=energy =force ×displacement =75×20=1500J

time=energy/power=1500/200=7.5 s

Answer 2

Answer:

7.5 seconds

Explanation:

We know that, Power is rate of work.

P = W/t

and W = force × displacement.

therefore, P = Fs/t

time taken to push the box,

t = Fs/P

t = (75×20)/200

t = 75/10

t = 7.5 s